This invention relates to an aerobic exercise machine.
Different types of machines exist for aerobic exercises and for muscle conditioning based on movement which is referred to, perhaps somewhat loosely, as elliptical. Some of these machines however offer only one exercise. The monotony of a single exercise can result in boredom and cause a user to discontinue the exercise. Also, repeated performance of one type of exercise is less effective than engaging in a variety of exercises.
A few so-called “dual mode” exercise machines have been developed. These machines offer a second type of exercise in addition to exercise based on the so-called elliptical movement. Usually though this is at the cost of complex design and additional expenditure. A further aspect is that a somewhat laborious process is required when reconfiguring parts of the machine in order to change from one exercise mode to another.
For example, a machine referred to as “SEG-1682—Two-in-one Elliptical and Stepper” (cf http://www.thane.com/service.php), has a footplate which is mounted to a slider. In a stepper mode the footplate is locked to a cross-member by means of a screw. Upon rotation of a crank the footplate is moved up and down in a vertical mode.
A similar construction is embodied in a machine, also from SEG, labelled “ED-3060—Motorised Elliptical Tread”. To place the machine in an elliptical mode a screw is loosened and a footplate is moved along a slider to a defined position at which the slider is locked against movement. Rotation of a crank then causes the footplate to move in an elliptical fashion. The crank is permanently connected to the slider.
A so-called “Street Bike” (origin unknown), (which is a mobile device and not a stationary exercise machine), includes a pedal mechanism wherein up/down movement imparted by a user to footpads is translated into rotational movement of a crank which has arms which are slidingly engaged with the footpads. This “Street Bike” offers only one mode of use.
An object of the present invention is to provide a dual mode exercise machine which is relatively inexpensive and which has a simple construction to facilitate switching from a first exercise mode to a second exercise mode. An additional important aspect of the invention is that the exercise machine cannot readily be placed in a situation in which neither mode is engaged. This enhances the safety of use of the exercise machine.
In this specification a first exercise mode is also referred to as a “stepping” mode. A second exercise mode results upon rotation of a crank around an axis. Movement is transferred from the crank via a footplate to a user. This movement may be circular or partly circular and, for the sake of convenience and in order to distinguish one mode from the other, is referred to as “elliptical” movement.